1. Field of the Invention
The present invention generally relates to image processing and, more particularly, to an image processing apparatus, a method thereof, and storage medium, and particularly to a technique for converting page image data into the page image data in tile sequence.
2. Description of the Related Art
For image forming processing, there has been a conventional technique for converting image data into image data for each rectangular tile, and then printing the image data at high speed by performing subsequent image processing in a tile unit in parallel. Processing for converting the image data into the image data for each tile is referred to as tile-sequence conversion processing. The tile sequence conversion processing is performed by inputting the image data into a work buffer in a page line sequence, and dividing the image data buffered at a predetermined tile height, into the image data of each tile, and then outputting the image data in tile sequence. Thus, in the tile sequence conversion processing, the image data needs to be temporarily stored in the work buffer and therefore, a predetermined buffer size is required.
Japanese Patent Application Laid-Open No. 2009-269355 discusses a technique for reducing a required buffer size by storing in the work buffer the image data in a vector format before the image data is rasterized instead of a raster format after the image data is rasterized, and then performing the tile sequence conversion processing on the image data in the vector format.
However, when the tile sequence conversion processing described in Japanese Patent Application Laid-Open No. 2009-269355 is performed on the image data in the vector format, for a page image including a great number of objects, the required memory size of the work buffer may be significantly increased.